FRANKFURT (REUTERS) - German police said a misunderstanding may have led to a security breach that prompted the evacuation of Frankfurt airport's Terminal 1 and caused delays and flight cancellations at Europe's fourth largest airport on Wednesday (Aug 31).

Police were questioning a female suspect who had entered into the departure gate area at Frankfurt, a major hub for international travel and home to Lufthansa, without completing the security check, a spokeswoman for the federal force told Reuters.

"Based on initial findings of the questioning, it looks like this may have just been an accident," she said, declining to provide further details until the interrogation was completed.

She also said police did not find any suspicious items in the departure area following the evacuation.

The security breach interrupted flight operations, delaying departures and forcing some planes to divert to other German airports instead.

Airport operator Fraport said around 100 flights were cancelled due to the evacuation. Operations at the terminal resumed at 1030 GMT, it said, adding that all passengers were asked to go through the security check again.

Lufthansa was not immediately able to say how many of its flights were affected by the evacuation.

In a similar incident, a Spanish man was arrested at Cologne-Bonn airport in May after bypassing the security check, also leading to flight delays.